Cooney, Sean, author
Australian Goverment Publishing Service, 1995
Buku Teks
Pitkänen, Pirkko
Springer, 2012
eBooks
edited by Brian Opeskin, Richard Perruchoud, Jillyanne Redpath-Cross
Cambridge University Press,, 2012
Buku Teks
Plender, Richard, author
Sijthoff, 1972
Buku Teks SO
Horwitz, Morton J., author
Harvard University Press, 1977
Buku Teks